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Home >> Ford >> 2017 >> Transit-150 Base, 3.2L Eng VIN V >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Pinpoint Tests (Diesel) >> Pinpoint Tests AF: Glow Plug System >> Test Procedure
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Test Procedure

  1. AF1 PRELIMINARY DIAGNOSIS 
    • Clear the PCM DTCs.
    • Carry out the KOER Glow Plug Monitor self-test.

    Are DTCs P066A, P066B, P066C, P066D, P066E, P066F, P0671, P0672, P0673, P0674, P0675, P0676, P0677, P0678, P067A, P067B, P067C, P067D, P067E, P067F, P068C, P068D, P068E, P068F, P06B9, P06BA, P06BB, P06BC, P06BD, P06BE, P06BF, P06C0, P138B, P263C, U0074 or U0106 present? 

    Yes No
    For DTCs U0074 or U0106, GO to  AF10.
    For all others, GO to  AF2.    		 For symptoms without DTCs, GO to  AF2.
    For all others, RETURN to SYMPTOM CHARTS for further direction.
  2. AF2 REPROGRAM THE GPCM OR UPDATE THE GPCM CALIBRATION 
    NOTE: Wait for 2 minutes before disconnecting the GPCM connectors.
    • Ignition OFF.
    • For Transit,
    • GPCM-A connector disconnected.
    • GPCM-B connector disconnected.
    • Visually inspect for:
      • pushed out pins
      • corrosion
      • damaged seals
    • GPCM-A connector connected.
    • GPCM-B connector connected.
    • Make sure the GPCM connectors are seated correctly.
    • Ignition ON, engine OFF.
    • Clear the PCM DTCs.
    • Carry out the PCM self-test.
    • If any glow plug DTCs are retrieved again, turn the ignition OFF and wait for 2 minutes.
    • Clear the PCM DTCs.
    • Carry out the PCM self-test.
    • For all others,
    • GPCM-A connector disconnected.
    • GPCM-B connector disconnected.
    • GPCM-C connector disconnected.
    • Visually inspect for:
      • pushed out pins
      • corrosion
      • damaged seals
    • GPCM-A connector connected.
    • GPCM-B connector connected.
    • GPCM-C connector connected.
    • Make sure the GPCM connectors are seated correctly.
    • Ignition ON, engine OFF.
    • Clear the PCM DTCs.
    • Carry out the KOER Glow Plug Monitor self-test.
    • If any glow plug DTCs are retrieved again, turn the ignition OFF and wait for 2 minutes.
    • Reprogram the GPCM or update the GPCM calibration.
    • Clear the PCM DTCs.
    • Carry out the KOER Glow Plug Monitor self-test.

    Are any glow plug DTCs retrieved again? 

    Yes No
    For DTCs P138B and P263C, GO to  AF4.
    For all others, GO to  AF3.    		 The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.
  3. AF3 CHECK THE SUSPECT GLOW PLUG RESISTANCE 
    NOTE: Use the component connector information to match the connector pins with the DTCs.
    • Ignition OFF.
    • Glow Plug connector disconnected.
    • Check for loose, damaged, or backed out terminals.
    • Measure the resistance between:
      (+) Glow Plug Connector, Component Side (-)
      Suspect Glow Plug Ground

    Is the resistance less than 2 ohms? 

    Yes No
    GO to  AF4. For Transit, INSTALL a new Glow Plug.
    REFER to the Service Information, Glow Plug System.
    Clear the PCM DTCs. REPEAT the self-test.
    For all others, INSTALL a new Glow Plug.
    REFER to the Service Information, Glow Plug System. Carry out the KOER Glow Plug Monitor self-test.
    Clear the PCM DTCs. REPEAT the self-test.
  4. AF4 CHECK THE VBATT CIRCUIT FOR VOLTAGE 
    NOTE: Wait for 2 minutes before disconnecting the GPCM connectors.
    • Ignition OFF.
    • GPCM-A connector disconnected.
    • Ignition ON, engine OFF.
    • Measure the voltage between:
      (+) GPCM-A Connector, Harness Side (-)
      VBATT Ground

    Is the voltage greater than 10.5 V? 

    Yes No
    For DTCs P138B and P263C, GO to  AF8.
    For all others, GO to  AF5.    		 REPAIR the open circuit. Clear the PCM DTCs.
    REPEAT the self-test.
  5. AF5 CHECK THE GLOW PLUG CIRCUIT FOR AN OPEN 
    NOTE: Wait for 2 minutes before disconnecting the GPCM connectors.
    • Ignition OFF.
    • GPCM-B connector disconnected.
    • Measure the resistance between:
      (+) GPCM-B Connector, Harness Side (-) Glow Plug Connector, Harness Side
      Suspect Glow Plug Suspect Glow Plug

    Is the resistance less than 5 ohms? 

    Yes No
    GO to  AF6. For Transit, REPAIR the open circuit.
    Clear the PCM DTCs. REPEAT the self-test.
    For all others, REPAIR the open circuit.
    Carry out the KOER Glow Plug Monitor self-test.
    Clear the PCM DTCs. REPEAT the self-test.
  6. AF6 CHECK THE GLOW PLUG CIRCUIT FOR A SHORT TO GROUND 
    • Measure the resistance between:
      (+) Glow Plug Connector, Harness Side (-)
      Suspect Glow Plug Ground

    Is the resistance greater than 10K ohms? 

    Yes No
    GO to  AF7. For Transit, REPAIR the short circuit.
    Clear the PCM DTCs. REPEAT the self-test.
    For all others, REPAIR the short circuit.
    Carry out the KOER Glow Plug Monitor self-test.
    Clear the PCM DTCs. REPEAT the self-test.
  7. AF7 CHECK THE GLOW PLUG CIRCUIT FOR A SHORT TO VOLTAGE 
    • Ignition ON, engine OFF.
    • Measure the voltage between:
      (+) Glow Plug Connector, Harness Side (-)
      Suspect Glow Plug Ground

    Is any voltage present? 

    Yes No
    For Transit, REPAIR the short circuit.
    Clear the PCM DTCs. REPEAT the self-test.
    For all others, REPAIR the short circuit.
    Carry out the KOER Glow Plug Monitor self-test.
    Clear the PCM DTCs. REPEAT the self-test.    		 GO to  AF8.
  8. AF8 CHECK THE CIRCUIT FOR VOLTAGE 
    NOTE: Wait for 2 minutes before disconnecting the GPCM connectors.
    • Ignition OFF.
    • For Transit,
    • GPCM-B connector disconnected.
    • Ignition ON, engine OFF.
    • Measure the voltage between:
      (+) GPCM-B Connector, Harness Side (-)
      ISP-R Ground
    • For all others,
    • GPCM-C connector disconnected.
    • Ignition ON, engine OFF.
    • Measure the voltage between:
      (+) GPCM-C Connector, Harness Side (-)
      VPWR - Pin 6 Ground

    Is the voltage greater than 10.5 V? 

    Yes No
    GO to  AF9. REPAIR the open circuit. Clear the PCM DTCs.
    REPEAT the self-test.
  9. AF9 CHECK THE PWRGND CIRCUIT FOR AN OPEN 
    • Ignition OFF.
    • For Transit,
    • Measure the resistance between:
      (+) GPCM-B Connector, Harness Side (-)
      PWRGND Ground
    • For all others,
    • Measure the resistance between:
      (+) GPCM-C Connector, Harness Side (-)
      PWRGND - Pin 5 Ground

    Is the resistance less than 5 ohms? 

    Yes No
    For DTC P138B, GO to  AF13.
    For all others, GO to  AF10.    		 REPAIR the open circuit. CLEAR the DTCs.
    REPEAT the self-test.
  10. AF10 CHECK THE CAN2 CIRCUITS FOR AN OPEN 
    • Ignition OFF.
    • For Transit,
    • GPCM-B connector disconnected.
    • PCM-T connector disconnected.
    • Measure the resistance between:
      (+) GPCM-B Connector, Harness Side (-) PCM-T Connector, Harness Side
      CAN2+ CAN2+ - Pin 35
      CAN2- CAN2- - Pin 36
    • For all others,
    • GPCM-C connector disconnected.
    • PCM-B connector disconnected.
    • Measure the resistance between:
      (+) GPCM-C Connector, Harness Side (-) PCM-B Connector, Harness Side
      CAN2+ - Pin 3 CAN2+ - Pin 56
      CAN2- - Pin 4 CAN2- - Pin 39

    Are the resistances less than 5 ohms? 

    Yes No
    GO to  AF11. REPAIR the open circuit. Clear the PCM DTCs.
    REPEAT the self-test.
  11. AF11 CHECK THE CAN2 CIRCUITS FOR A SHORT TO GROUND 
    • NOx11 Module connector disconnected.
    • NOx12 Module connector disconnected.
    • For Transit,
    • Measure the resistance between:
      (+) GPCM-B Connector, Harness Side (-)
      CAN2+ Ground
      CAN2- Ground
    • For all others,
    • Measure the resistance between:
      (+) GPCM-C Connector, Harness Side (-)
      CAN2+ - Pin 3 Ground
      CAN2- - Pin 4 Ground

    Are the resistances greater than 10K ohms? 

    Yes No
    GO to  AF12. REPAIR the short circuit. Clear the PCM DTCs.
    REPEAT the self-test.
  12. AF12 CHECK THE CAN2 CIRCUITS FOR A SHORT TO VOLTAGE 
    • Ignition ON, engine OFF.
    • For Transit,
    • Measure the voltage between:
      (+) GPCM-B Connector, Harness Side (-)
      CAN2+ Ground
      CAN2- Ground
    • For all others,
    • Measure the voltage between:
      (+) GPCM-C Connector, Harness Side (-)
      CAN2+ - Pin 3 Ground
      CAN2- - Pin 4 Ground

    Is any voltage present? 

    Yes No
    REPAIR the short circuit. Clear the PCM DTCs.
    REPEAT the self-test.    		 GO to  AF13.
  13. AF13 CHECK FOR CORRECT GPCM OPERATION 
    NOTE: Wait for 2 minutes before disconnecting the GPCM connectors.
    • Ignition OFF.
    • Disconnect all the GPCM connectors.
    • Visually inspect for:
      • pushed out pins
      • corrosion
    • Connect all the GPCM connectors and make sure they seat correctly.
    • NOx11 Module connector connected.
    • NOx12 Module connector connected.
    • Carry out the GPCM self-test and verify the concern is still present.

    Is the concern still present? 

    Yes No
    INSTALL a new GPCM. REFER to the Service Information, Glow Plug System.
    CLEAR the DTCs. REPEAT the self-test.    		 The system is operating correctly at this time.
    The concern may have been caused by a loose or corroded connector.
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